Race in a 2.5 inch split short if you want the least fabric possible on the track. Train in a 4 inch split short if you want one pair for every workout, and pick half tights (about a 9 inch inseam) for long runs, cold mornings or thighs that rub.
We make all three: the RD 2.5 inch, the LD 4 inch and the MD Half Tights. Here is how they compare on paper, and how to choose by event, workout, build and comfort.
By Parker Dewey
The three cuts side by side
Specs come from our product pages and size charts. Any 2 pairs of shorts get the 3rd free, and you can mix cuts: the lowest priced pair comes off automatically in the cart.
What are split shorts?
Split shorts are running shorts with the side seam cut high up the leg. When your knee drives forward, the fabric opens instead of pulling against your thigh. Add a built-in liner and a light fabric and you have the classic track and road racing short.
RD 2.5 inch split shorts: the least fabric you can race in
The RD Split Shorts are our shortest cut: a 2.5 inch inseam, a high split and featherweight fabric. The outseam is 10 inches in every size, so on a taller runner they sit higher on the leg than on a shorter one.
Get the 2.5 inch if you:
- Race 400m to 5K on the track, or road races in the heat.
- Want nothing touching your thighs at full stride.
- Already own longer shorts and want a dedicated race pair.
Skip it if your inner thighs rub, or if you want coverage for warmups, team photos and the walk back to the tent.
LD 4 inch split shorts: one pair for every workout
The LD 4" Split Shorts use the same featherweight fabric with an extra 1.5 inches of inseam and a relaxed athletic fit. The side split still frees your stride, and the same two gel pockets sit in the liner.
Get the 4 inch if you:
- Want one short for intervals, tempo runs, easy days and race day.
- Find a 2.5 inch too short, but want to stay in a split short.
- Have a small waist: it is the only one of the three that comes in XS (27 to 30 inch waist).
At $45 it is also the lowest priced of the three.
MD Half Tights: locked in, with room for a phone
The MD Half Tights are a different tool. The ribbed fabric fits snug from waist to mid-thigh, about 9 inches of inseam, so nothing flaps and your thighs do not touch skin to skin. They are the only cut of the three with a phone pocket: a zip pocket on the back, plus two inner gel pockets.
Get half tights if you:
- Run long and carry a phone and a couple of gels.
- Chafe between the thighs in shorts.
- Run on cold or windy mornings and want more coverage.
- Like a compressed, held-in feel.
In real heat, most runners are cooler in a split short. If your size or color is sold out, MD Half Tights preorders open soon. For a comparison with other brands' half tights, see our running half tights comparison.
Which cut for which event and workout?
How to choose by build and comfort
- Your thighs touch when you run: half tights. A liner protects under the short, but only a tight leg covers the inner thigh.
- You are tall: the RD's 10 inch outseam is the same in every size, so it will sit higher on your leg. If that sounds like too little, go 4 inch.
- You want coverage without compression: 4 inch.
- You carry a phone: half tights. The split shorts hold gels, not a phone.
- You are not sure what length you like: take a pair you already run in, lay it flat and measure the side seam from the top of the waistband to the hem. Compare that number with the outseams in the table above.
Should running shorts be tight or loose?
Both work. Loose split shorts run cooler and move freely. Tight half tights stop chafing and keep everything still. Plenty of competitive runners own both and pick by session and weather.
Do you wear underwear with split shorts?
No, not with a built-in liner, and all three of ours have one. The liner replaces underwear; an extra layer adds seams and holds sweat.
What to look for in any running short
- Inseam matched to the session (see the tables above).
- A liner that sits flat and does not bunch.
- Pockets where they do not bounce. Pockets inside the liner hold a gel against your body.
- A waistband that stays flat. An internal drawstring lets you tighten it for race day.
- Sizing by waist measurement, not by your jeans size.
Sizing and returns
Measure your waist and use the chart for each cut: RD 2.5 inch sizing, LD 4 inch sizing and MD half tights sizing. If you are between sizes, size up for a looser fit. For the half tights, stay true to size if you want race-day compression.
Wrong size? Running gear can be returned or exchanged within 30 days of delivery, unworn and unwashed with the original tags. Details are on our returns page.
The short answer
- Racing on the track or in the heat: 2.5 inch.
- One pair for everything: 4 inch.
- Long runs, cold days or chafing: half tights.
Shop all running split shorts or men's running half tights, and mix any three pairs for the price of two.
